since it has a diameter of 6, its radius must be half that or 3.
[tex]\bf \textit{volume of a cone}\\\\ V=\cfrac{\pi r^2 h}{3}~~ \begin{cases} r=radius\\ h=height\\ \cline{1-1} r=3\\ h=6 \end{cases}\implies V=\cfrac{\pi (3)^2(6)}{3}\implies V=18\pi \\\\\\ V\approx 56.5487\implies \stackrel{\textit{rounded up}}{V=56.6}[/tex]
